Automatic or semiautomatic telephone system



NOV. 3, 1931. p wRlGHT 1,829,774

AUTOMATIC OR SEMIAUTOMATIC TELEPHONE SYSTEM Filed May 26 1930 3 Sheets-Sheet 1 FIG. I IA 7\ A 2A J "J FIG.2

INVENTOR ESMOND FfGWRlGHT WM M ATTORN EY E.'P. G. WRIGHT 1,829,774

AUTOMATIC 0R SEMIAUTQMATIC TELEPHONE SYSTEM Filed May 26 1930 3 Sheets-Sheet 2 wslllllll T H ll m :3 RM mllllllll Li 0 0% g E E m mm u- E\ Mk 4 E D i w. k w\ m E Q\% 1 llll m Q U 11ml I E & 7 -& b m WE bm Mg .3 m3 m hm n) n 2 MN m5 VJ Ed .nfi Q m n E m u 41G w u m M q u a 1 New w 1 NM hwm WWI; .WTY v m 11.- 3 .wwlml M w@ 2% m%% MQ 9w x ku 1% 1 1,. 2m 1 T L 1 w I km it 1 mUi$ RH; m NW N OE Nov. 3, 1931.

ATTORNEY NOV. 3, 1931. 5, wRlGHT 1,829,774

AUTOMATIC OR SEMIAUTOMATIC TELEPHONE SYSTEM Filed May 26 950 3 Sheets-Sheet 3 FIG. 4-

INVENTOR ESMOND E G. WRIGHT ATTORN EY I ,EsMo n 1 mm eooiiwm, 'wmcnn or f This Jamal-{rei s to, automatic as l atentid I ALDWYGH, LONDON, ENGLAND, AssiGnoR TO jINTERNATIQfi'AE:STANDARD 'fn'nncrmoconronarion, or'nnw YORK, N. Y.

" f ,nuroMAri'Io 0R "sEMmUroMArIc TELEPHONE f SYSTEM Applicatioii liled m y. 26,1930, Serial 1105455537; and' i semi-automatic telephone, systems, in, which means is provided at one-or more selecting stagesv to determineinlflpart theoutlet or li group of outlets to'be tested in accordance, Withthe path ofentryinto the switch.

The main feature of the'invention com prisesfa circuit ,arrangementfor an autosystem comprising selector switches, characterized in this,,that discriminatmg means is provided which is associated in common: I Wit-ha plurality of said switches andwhlch is adapted to be o'perated variably in ac wcordance with the path. ofaccess .used

setting up a connection. i

' The invention ywill be described re 1 spect, tofa selector system :in which. the con- "versational switches arerarranged in groups each jgroup, being associated witha single- 7 control circuit.

'1 group of outlets in the banks of the select-V idle oriwanted'koutlet inthe-banksof the. c'onversationi switch in use.-

" 1 switch has performed its-markingfunction, ithunts for the'selected conversationl'circuit vand connects the controlcircuit thereto. A

The control circuit comprises two switches,-

y other a,'selecting switch, 1 1 The'marking sw tchis set inresponse to digitalv impulses and marks an outlet or one of whichis aimarking, switch, and the ing switch,which;in' turn marks, the selected temporary bye-pathjs set up throughthe second switch in thesucceedingIbye-patht ,7 The bye path orselector switch selects an idle Qbye-pa thf, control circuitftogether vwith an, associatedidle conversation circuit in the, succeedingselecton -stage and forms a item} j poraryQ bye-path icircuit to the succeeding I control circuit. ,A ll=the switches used are of' the single-motion type.

ye-Path r t s-i 1 Fig, 2 shows a selectorf'stageconnected to one of a plurality of final stages each com- 59, pri singtwo groupsjofgswitc'hes"in parallel. I I

j inatic or semi-automatictelephone exchange IBQis combined [toi'pass After the first Fi grfll shows schemat cally the lay out of 18mm may not 6 a sysqm of the ikind referred to witlija com'-' nion switching stage: and conversational and 11 Great mma J une 5, 192a Eig. 3.shows a conversational switch and bye-pat I circuit at an intermediate stage Fig,- ashows a final conversational switch andbye-path circuit. 1 f a [llheproblems to which the" embodiment of the "invention to be described relate concern the provision-of switching meansforobtaining access to stations or trunks the;traflic to which- 1is small, and

for which therefore a small number of access switches are requ red; Instances that may-be given are,

special service stations such as complaint, enqu ry, andfault operators, and junctions leading; from .a town exchange to a number of exchanges the traffic .to which issmallv he formercasewill be, discussed in more detail, with reference to Figure; l of the :ac companying; drawings, In this case: traflic from, two, directions through switches 1A; 7 through a common switching-stage 2A, conversational and bye path routes beingshewnin each case.

QIt willy-be supposed that the switching stage QAisreached over two or more difierof outlets of theswitchingstages 1A,.1B, and into corwthrough 2A ent outlets or groups that the digits dialled may be identical for difierentnstations reached thereover. It will" .be se'e'n therefore that discrimination is necessary inYQA in accordance with the outlet from thepreceding stage. I

Thefcontrol.or bye-path circuit associatedjlwith 2A is taken into use from the R2 or selector. switch of 11A or- 1B, and relay A alone or relays Aland Dare operated, Re

lay 4D I the discriminating-I: relay, thekmarking switch R1 marking its R2 switch dif ferently in accordance withtheipositionjfof p t k t s, It will be appreciatedr' th at if the stage 2A is a iinal' stage; for example, certain of the digit co1nbinations, which could t be used, required 'in which case fewer outlets than usual would be necessary therefrom., N f

'Inthe particular exampletobe described with reference to Figures 2, 3 and 40f the accompanying drawings, of which Figure 2 isa layout drawing, theinvention is described 1 with reference to anautomatic or semi-auto- .i gl l p c 9 hai th re i'i alu sg th ifi st gr upiinb lk f 'respectivelyfand sofonj.

the same dig ta s r's fililin bank .6 by contact 2915 h i l 0fR-l,th

{HQ-is marked" by iiconjtact' ,2 in bank 9 of R1,"

" 'releyJJ decides Whif liset of ar g conpositions in banks I .ductjors is to ive used by its ,Contactsfjy'E-B' in c 'r'tlan ewith ip th oia 'ce s Th a ins an e. a cord nce h he r b byiat narking conductor'to the contactinb'fln ps ffor example, contact 2 ankilO, of R1 to contact? jofbankG of Raand so on. After the switch R2 is set to th'ecorrect group of outlets it but if alltheoutletsarebusy,

hunts for an idleoutlet as will be described, to prevent the switch continuingto hunt for anidle outlet infthenext group. For this purpose the contacts/in the" group the banks of R2 are nlultipled toot' armature; e8 of ;relay to form acircuit,

ecl'osure ofwhi'ch' stopsthe switch as dew i 11 geese w w i T d sita v i de ign t g t e g o ps; of outlets" from R2 may be any desired five only inj banks 9 and {marking pur'posesr,

tact 0, bank contact t nce, M '68 to ground liThj ewillcauselthel 7096mm e r l yMaind the opening of,

values out. oft-he When the. R2 switch I startsgstepping itf'will'in time reach a si-"r ti'on'in which a circuit f-Will be completedfor the relay through'l 7th wiper and bank conthefdriving circuit magnet R2 by m1. .lf f rth "impu qu'ent operation ofthesyvitch "R1 will open j the circuitiiofirelay Mthereby permitting" {the switch '32 to continue stepping. When the digitis finished, and R2 finds the contact ,ji ipg ze i and Wfl t' erbte. 0pm th drivi g finally marked lbyRl; relay M agaln enercirciiitof "R2 already "explained? IWhQen th ls w ielay G'r lea aa "fore be' 'completed for the'relay Ethrou'h contacts 92,1 02, .ZL2,1th'e Wiper 'N and its 1 1' Yl fnq e 91 p tqg un The re ay;

em t will there- E closes a circuit forj the'switch R1 through ffconta'cts 61 375.64 interrupter) springs, V and oif. normal bank.contact'j3 it2 'toi Wip r a 7 third nd f r hg oui s in bank .0 (by contacts-3 in banks 9andf The discriminating ,2. corresponding to ,the first outlets of.

it is necessary v 7 bank C ofRQv corresponding to thef1ast outlets of each n v pl and c0ntact h7 then gether and are connected to the front contact p p p tbo 'on the. test Wire,

,o'p'erating 'circuit of relay Q,

possible ten, thus values 2, p used, according to circum stances. Itmaybejthattwo orthreegroups'f lofoutletsf only arerequi'red for each path of access in'which case; two or'three contacts 10 ofiRl'will be'used forv fan di wiper 10 for i'n-"cuit would be,

- simultaneously,

are received the subse l, ro n T e sw t h 1 nt u te pi a e rel y; Tfopere sx r a c r uit which wil b I 'd scribedljater; RelayjE alsoclosed'the testjcirc'uitcfor'relays P and Q a e9, 6110 and opened at 'e8 ,jthe operating circuit of re lay Therelease of relay closesthe c'i'r- 7 ictiiti fojr the sWitchRQ and as a result the outletsl'yyill betested twoata time. The contacts inthe banksTl; Will be connected to the e iwi s ff e rrespo ding! filial It versjational svvitche'slifallft he outletsiare busyrelay M will re-operate at the last set of terminals [of the, group of contacts, over 7L6,

w rsr 'a d enk c nt ct! of he w t 68 to ground; A circuit is then closed for rel y .G'p ro lg' co ta t pe an'dLofi-normal are N, 91, plto ground; Re

lay G is of high resistance and slow to operate, and consequently a time period pro,

vid'ejdf-toenable relay P and Q to operate if thereisa circuitjforthem. The operation 7 of relay M prevents R2 taking any further steps. If one of the outlets searched over 'by the'wi'per T1 is free,'relay P will be operated from "battery in the succeeding bye-pass switch over bank contact and iper T1,e9, P, g5, $65 to ground'] at wi i s relay Relay P closes'the circuit for the relay H' at opens the circuit of relay Pand places a ground potential from contact 7L8 opens the, and contacts b5 aud t/t6 prepare a marking circuit for the 4 conversationalswitch- Contacts he close an irnpulisi'ng circuit to the succeeding bye-pass,

contact h3-provides a'locking circuit for therelayH to earth at 62, contact Z712 opens the operating circuit of'relay G andcontact 7L1 opens'the localimpulsingcircuit. If one of the outlet-ssearched over by the Wiper T2 was foundgto' be free relay Q would have operated'in asimilar manner, J over the obvious circuit and relay Hover contacts jlfg'l, p1. Relay J provides a Wi er {discrimination j and when operated the orward ilnpulsingcircuitand the marking cir set'of contacts. I'f'relays P and Q operate there. will beno circuit for operating relay switched over to the required relay J andrelay 'H will operate alone. It

will 'be seen that corresponding contacts in both marking'levels' 11', I2 leadover the I path access tothe final bypass. The operation of relay T will'take pl Whichhas been predetermined. As already "explained the ground potential is placed on the hold conductor which is extended over the obvious circuit for the relay TB and closes a locking circuit throughv contacts t1, $163 a'ndbQ .toground." Thcrelease of relay.

ace when theswitch R1 reaches thecontactcon .responding to the conversational "switch 'alBalso removesjgro und fronithe bye-pass test conductor thus releasing supervisory.

",iiis' se'w xdfwwiindinglat co t cts 4 .7 e' el ylkietiiy I operation ofirela V i fif the test circuit,- Qwi I purpdsew11ipii will be-ideserib'edlaterz' i the units--iIhD1ilsesf-commence a is closedfor theniagnet RAl "and thisfsjwitch th'eendf of thejun'its{impulses closed? for tlie lnagnetf i through: its int er'rufpften'sj prin gs; contacts m2;

: 'Wsecbnd contact: }-arc "13 22) and-wiper 3 I V I tacts M1, maiy'pai a2jtoground and switch (co er j'i b s V @Jf'the'uni-ts digit was e,;.re1ay;MA would operate immediately reached 1 position I V 22 earth,- ca l, MA, 215x73 .wipe'r'95 contact1 22;

battery. The operation *of -MA would 3 pre-' vent switch RAfi s teppiii-g on, sothat the I v a, ;switch*wouldreniain Orr-the first contact of i the' group which {'coi're's'po'ndsto "units digit 0?; I When relay' 'MA does operate the following circuit jis closedlfor relay EA; bat

' tery and winding of the relay EA, baDkJCOI I tact-(and. wiper diet the switchRA'Lfconslow' to release type andfdoes' not: release irn- V '36 mediate-1y. Meanwhile a;; c1rcu1t 1s"closed from ground, batyove'r 'the wiper and bank contactz18'fof switch RA e429, 9618, windi1 1g o thetest wip'er. The A', l' JA-fi'n' jcontrollingthe line called isffree relay PA will operate," contact W15 closing the obvious circuit for" relay-Hawmch will'he provided with a l0ck-' 7 ing"circuit throughlcontacts1W2; When thef @conversational switch isfound, as described later, --gr01'1'nd' is1 connected to the hold wire ;due to the operation of-HS. The contact on '7 "which whderHthefi stands i's multipl ed; to]

'the contact of RA2't'owhich relay PAf'is con: ia ne'cted so that-'- PA I will then be short-cirfcuite'd"but HA willhold via ha2, ma1, pal; It will be seen'thatfthefcontact' ya? extends ground from bar/4" to: the bye-path test con ductor' after relay 'EA operates'openingfthe v fio path through fcontacts;e627; Gonta'cts 7z'a5T to the testwire over-contact 7M6. The

ground on the' hold wiper is also extended replace thepat'h which wilL-be opened when' the: relay GA releases" duetdthe operation of 7 relay EA; and contacts-M7 "openjthe circuit of relay. MA'-*which,release'.- If the calledsubscriber-"s lineisbusythe releaseof'relav ai di rz f t e sw t h i. on 7 6.." 1 m2; H25. itofl'ground. i *As already explained i relay BS "closes"thecirc'nit for the" relay AS fig' and', applies busy tone to the calling ef'switchjRAL conbe described later. "If! When the switch'RI, Fig. '3; made connection 1 j with the "selected path, a 1 relaywas operated at; the operatorsposition ,so that the byein lthe final'bye-pass operates duetothe called will again step, when the-relay GA releases,

. a in? 7 A sulb'scribersf line beings-tree the swltch RAl -RA-2fcontinues st'epping1 intil tl 'e'circuit al- I ready described for again closed."-

over its; interrupter springs,- contacts "ealg g(43, ta2 'maQ- to gro'undfuntil-it reaches the conversational switchindicated 'by a ground potentialfon the hold conductorflylhis cir-I cuit niaybe traced from battery, right hand" J winding of the relay TA, non-inductive resist'ance; wiper and bank l ofthe switch HA1, V

coiitacts'fhsl, bankcontact and wiper H of the penultimateconversational switch, 985 to' ground." Relay TA locks up over its second windin g 'tm; to ground at ba /2. The relay" TARalso closes thefollowing circuit for the final selector switch SA'through' its interruptersprings, bank contact and wiper 6 of the" switch RA1, -h a4,;;m2,-ma2to ground.

Theswitch-SA has access to all thei'lines tested by 3A2 and the contacts correspond ing to the salnelinein bank M of SA and" banks" M1, M2, of HA2 are 1 connected by marking "contacts Thexfinal selector hunts i i for the' line sel'ectedby RA2 and'whe'n this is found a'ci'rcuit'is closed for the-relay MA? 'gr o7und{ cafi'winding of the relay -MA, mp5, he

wiper-M of the final-selectorthank'contact' 9j oftheswitchBAl, h'a8,'ta3,' to battery; Re

scribers-line; Relay HS'locks up over contaCtsf bs-Q, wiper andbank contact H of the conversational switch tothe ground supplied by the operation of contacts hsl to the hold wiper ofthepenultimate path; Contact 71,85; 1

ho'weve ggo'pensthe bye pass test conductor thereby droppingrelay E in the penultimate bye-pass; The grelease of 'relay E in the pe-' nultimat'e' bye path opens the circuit ;of relay GS which'jis slow to release and thereby providesia 'perio'd during which ringing 'cun,

rent supplied to the called party. This ensures th'atiringing tone is applied iinmedi ately'theconnectionis switchedithroughzandi obvia'tesfthe"possibility ofdelay'jwhich'oc Y i v curs when only]interrupted" ringingfisfsupp'liedi 'Whenytherelay GS has releaseda:

10c ja5',fwiper and'fban'k'contactfM'l or'M2 1 of the "switch; HA2, the bankYcont-act and 1O v 'iary control circuit which is associated with both groups of switches and which comprises ance with the path-of access used todetermine in part the selection of the wanted outoneofsaid switches to be used in setting up a; connection'and to be operated, in accordlet' or outlets of the said-switch. I

2. In or for a telephone system, a group ;ferent group of outlets 'or'lines andan auxildiscriininating' means adapted to operate when the said circuit is in use for setting up; a connection over any one of said switches in a manner, distinctive to theparticular group of switches involved. I I

3. A telephone system ,co;mprising a group ofconversational switches, a plurality ofdifferen't paths over which each of said switches is accessible, and discriminating means common to said: group of switches adapted to be by series connected to any one of saidswitches in re sponse to the initiation of a call thereover, to be operated in accordan'cewith the path over I *hich the callis made and to be released upon establishment of the call. 4 A telephonesystem comprising a group ersational switches, adapted to be set t in1pulses,a plurality of paths over W111i Ch eac of said switches is accessible, and discriminatii gl m comm to S group of switches adista w be @Qnnected t e one of said ggrr response to the initiation of a call stems n to e operated I prior to the receipt of sais se of lmpulsesi in accordance with the patltQffi-t lvblch the call is made.

matic telephone system,

witha number'of said switchesand con, pglscs H 7 l I iso aca marking switch, p l ll y P x Icess tosaid selectorswitclies and associated control circuits and discriminating means in the control circuit which is adapted to be opcrated in response to the path of access over which the common control circuit is taken V 1 into use, sa d marking switch being adapted t ark different outlets or groups of on lets from the said selecting stage in response to th same digit or digits received thereby in accordance with the setting of the said disti urinating means. I p

6i In or for an automatic or semi-automatic telephone system, a selector stage comprising conversational switches'and a pluralityof sociated in common with a pluralityofcom versation switches and comprises a 'marking -switch and'a bye-path switch havinga plu- .rality of sets of wipers, a plurality of paths of accessxtosaid selectorstage, discriminatmeans'in thebye-path control circuits b -path control circuit's'each of which is-as-' which-are adapted to be operated in accordance with the path of access over which the control circuit istaken into use and wiper switchingmeans which is adapted to select one of said sets of wipers in accordance with the setting of said discriminating means.

'TfCircuit arrangement as claimed in claim 6, in which each-bye path switch comprises a plurality of pairs of test wipers one of which is adapted to be selected in accordance with the setting of the discriminating means and further wiper switchingv means which is adapted to be operated in accordance with the odd oreven value of a digit received by said marking switch to select one of said pairs of test wipers.

, "In an automatic orsemi-automatic telephone "system, a selector stage, switching means which is adapted to be operated to connect continuous ringing tone to a selected line for a predetermined interval and further switching means which is adapted to connect interrupted means to said line after said cess to said final selecting stage, discriminat- 1 ing means in said control circuits which are adapted to be operated in response to a path 7 of access over which the circuit is taken into t per switchingmeans WlllCl'l' is adapted "$6111 *5. In or for an automatic oi s 1 all I a number oii nvei sational switches, a'plurahty of contiol circuits each ofwhichis associated in coal tion to select one of said levels in accordance with the setting or" said discriminating means and switching means which is adapted to be operated when the P. B. X. level or one of the P. B. X. levels is selected and in response to bye-path control circuit, which is adapted to operate in accordance with which one of the said groupsis involved in a connection and a single-motion by-path switch in said circuit'which comprises a test level or levels cor- }i esponding to each of said sets of outlets,and a common marking level or levels for controlling the setting of a conversation switch of either group, the said discriminating means being adapted to control the selection oftlie 

